The goals of the Biostatistics and Data Management Core (BDMC) are to provide biostatistical study design and analysis support, clinical epidemiology expertise and data analytic services to enhance the quality of the work performed by all of the SCOR investigators. moreover, this BDMC will provide comprehensive clinical data management and research computing services for the Clinical Research projects within the SCOR. A broad range of collaboration will be provided. Core members will be involved in all projects through assistance and advising regarding study design, biostatistical analysis, interpretation of results, and manuscript preparation. The aims of the BDMC are to: 1. Biostatistics a.) advise investigators on study design issues, including sample size/power considerations, for basic science/laboratory studies and clinical protocols; b) conduct statistical analysis of data from laboratory projects and clinical investigations to address specific research hypotheses define din the project-specific proposals; c) assist with preparation for and writing of final reports, abstracts, manuscripts, and future research proposals; d) conduct exploratory analyses that may lead to generation of new hypothesis. 2. Data Management a) provide the analysis, design, development and implementation of both an internal and distributed Data Management System (DMS) supporting the ALI/ARDS Registries within Core A (Clinical Core); b) design, develop and implement the DMS for the prospective cohort studies in Projects 1 and 3, and the nested case-controlled studies in Project 3; c) design, develop and implement the DMS for the randomized clinical trials in Project 3; d) provide training and assistance for project-specific research staff in the conduct of each protocol and in the use of the DMS; e) conduct all phases of quality assurance, validation, query resolution and reporting for clinical research protocols; f) create valid datasets for high scientific quality, combining the data from study-specific sources and from the BDMC, for biostatistical analyses.